Grady 275 Freedom rolling issue

I have a 335 Freedom. Installed automatic tabs from Mente Marine. Works great. I never have to adjust. Look at them online.
 
Thanks Natale for mentioning another option to Bennet Auto Tab Control!
The Mente system is basically the same as Bennets Auto Tab Control for their trim tab system using hydraulic pump and trim tabs.
The Seakeeper Ride system is same as Swedish ZipWake ans American Humphrees interceptor or blade bases system what is much faster in reaction as the Interceptor blades need around 1 second from retracted to full extension while trim tabs need many seconds to do the same.
Trim Tab based auto control works well for list control and keeping boat at a set planing level, but is slow, too slow to react to quick changing sea conditions like choppy sea or people moving around the boat at planing speed.

Chris
 
Twins or single on the 275 and what prop. I would expect both to impact the sensitivity to trim stability.

While using the same concepts for a variable deadrise hull, unsurprisingly each model has different dynamics. I use a lot of tab on the small 208 in head seas with lots of small adjustments. Prior owner installed the Bennett auto tabs but I don’t use that feature. My thinking is on a short boat like the 208, you really need the bow to work because ithe dead rise flattens out pretty fast. I use a prop that gives a bit of stern lift and am considering bigger tabs over the winter. 208 tabs are trailing, not in pockets.

Good luck with your 285. A friend of mine has Seakeeperon his 23’ Sportsman CC and says it is a game changer for him, while another friend with a new (much bigger) 30’ Pursuit DC says not so much.
 
Peter A said:
My thinking is on a short boat like the 208, you really need the bow to work because ithe dead rise flattens out pretty fast. I use a prop that gives a bit of stern lift and am considering bigger tabs over the winter.
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The GW SeaV2 hull design works as you describe, if sea is choppy the boat runs well with the sharp bow down, slice thru the waves and sit on the wide and not too high dead rise stern, a kind of plowing thru the waves. At least mine but i expect same for shorter GW's.
I still believe that a outboard powered boat shorter than approx 28 ft should not need trim tabs if weight on boat is correctly distributed and that running angle should be controlled by engine trim and not by trim devices.
On all my boats below 30 ft i did not had trim tabs (and in Europe new boats usually they don't come with them) nor did i missed them, in case of too light bow i simply shifted weight forward. In case of my 30ft RIB what i used mostly alone i added 50 gallons of water in a bladder tank inside the bow locker and her riding quality turned from night to day as the added weight corrected the incorrect weight distribution of me alone on the boat.. Using stern or bow lifting propellers will also help with making engine trim working better.

There are boats below 30ft needing trim tabs by nature, but this is either a design flaw of the hull happen frequently on older hulls made for 2 strokes and then repowered with heavier 4 strokes what makes them stern heavy due insufficient buoyancy on boats stern.

However, SK Ride, ZipWake, Humphrees and all the new emerging companies interceptor blade and advanced auto trim control is a different beast and can not be compared to trim tabs. Both provide control of boats yaw, pitch and roll but interceptor style trim devices are so fast in their movement that the control unit can keep boat on level even if sea is choppy or people moving around. Similar to a Gyro, but SK RIde works best if boat is on planing speed, as trim tabs effect on lower speeds is not very strong for either, trim tabs and interceptors, whhile a Gyro stabilze the boat also when on anchor or drifting.

Chris
 
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